4. Washington

The biggies are easy to spot -- Microsoft(MSFT) and Amazon(AMZN) are based there, and Boeing(BA) has huge manufacturing facilities in the state.

But a plethora of smaller firms have sprung up to supply or compete with these industry giants, and they have also contributed to the state's strong growth rate, said Steve Lerch, who heads the state's Economic Revenue and Forecasting Council.

The slowly recovering global economy is also helping Washington, said Lerch, as much of the software and aerospace items made there are destined for export.